Blazer running terrible

I bought a 95 blazer 4.3 V6 a few months ago it had a blown head gasket and i had that repaired it ran pretty well for a few weeks after that now it runs very rough on idle and smells very badly of gas i have a replaced the spark plugs, the wires, distributer, rotor, and has a new exhaust system on it whenever the car is stopped it runs very rough and sometimes misfires however once i hit about 40 mph it stops misfiring and runs much smoother it also had a gas leak in a pipe coming from the sending unit the leak is pretty much fixed but it drips a little from time to time my machanic cannot figure out what is wrong with it i have been told possible egr, the spider, cpi, how o i know what to replace? also the drivers seat is power and it does not move there is no power in the wires going to the motor all fuses are good what could that be?

is this what I have to look forward to? Dang.

The gas smell sounds like either the catalytic converter or 02 sensors. Definitely fix that gas leak now! These things are sensitive nowadays and that could be causing alot of your problems.

You need to replace either the fuel pressure regulator or the internal fuel lines under the plenum. My advice REPLACE THEM BOTH. I did this on my blazer and it runs great now and the gas smell is gone. Go to www.lindertech.com. You can purchase the pressure regulator for $99 and the internal fuel lines for about $50. Good luck. This is a very common problem with the Blazers.

i had same problem with my 94 and it was the fuel line cracked on the inside of the air plentenum i found it by looking at mu plug on the drivers side and they were soaked with fuel ,found out this is very common

when you take off the upper plenum how many bolts are there for some reason i cant seem to get it off

9 bolts... 10mm heads... Check for signs of washing... If the passenger side is washed (where one side is cleaner than the other) It's your CPI, if the driver's side is washed, it's your nut kit... If you replace the CPI, with that many miles you should just go ahead and replace the nut kit as well..

02 sensors should be replaced every 65-75k

took off the upper plenum and the drivers side is like pure black and the passanger side is alot cleaner yet still dirty and has some gas in the passanger side thanks alot for all the help

You need to replace your CPI, it's leaking..

New replacement injection units have the injector and pressure regulator in one unit. Try turning on the key and watch for gas spraying out of the inner fuel lines, be a very fine mist. These lines are actually called a "nut kit" named after the person who invented this mess of an injection unit. Good source for all this at good prices is www.rockauto.com